EFFECT OF CRITICALITY ON WETTING LAYERS - A MONTE-CARLO SIMULATION STUDY

A solid substrate, when exposed to a vapor, can interact with it in su ch a way that sufficiently close to liquid-vapor coexistence a macrosc opically thick liquid wetting layer is formed on the substrate surface , if such a wetting transition occurs for a binary fluid mixture in th e vicinity of the critical end point of demixing transitions, critical fluctuations lead to additional long-ranged interactions (Casimir for ces) within the wetting layer, changing its equilibrium thickness. We demonstrate this effect by Monte Carlo simulations of wetting layers o f a symmetrical Lennard-Jones binary fluid mixture near its critical e nd point. The results suggest that the effect should also be detectabl e in corresponding wetting experiments.